Center drive double end turret lathe



March 5, 1940. w. F. GROENE ET AL CENTER DRIVE DOUBLE END TURRET LATHE Filed se i. 27, 1931 16 Sheets-Sheet 1 $5 N Q I! m WMJILW :HH ..r. W mm mm Wm W N I M 4 5 my z. z 6/ I no I. 00 A I; \IY zzlzimz.55 :EEiIEIEEfi M mj a an 7 Q a v Q t m n o o .a a @m o o o o f a 0 mm 9 S 4 V $0 0 mm Q o 09 P 5 2. 2 Q o z m; M 3 i 5. ON 0 0 T a r: r: 9 wt E 09 m Q r March 5, 1940. w. F.'GROENE ET AL CENTER ERIVE DOUBLE END TURRET LATHE Filed Sept. 27, 1937 16 Shets-Sheeg 2 INVENTLWS. WILUAM F. GROENE c. E Z

or m ri o HAROLD J-SlEKMANN M) EGMXM ATTORNEY.

March 5, 1940. w, GROENE AL 2,192,436

CENTER DRIVE DOUBLE END TURRET LATHE Filed Sept. 2'7, 1937 16 Sheets-Sheet 5 3G W ea LS-S H ll 53 n l l I l L L 4 Sq llhmml w 1' INVENTORS. i wmum F. GROENE HAROLD lsmKMANN ATTORNEY.

March 5, 1940. w. F. GEfiE ET AL 2,192,436

CENTER DRIVE DOUBLE END TURRET LATHE Filed Sept. 27, 1937 16 Sheets-Sheet 4 a 4 g m z, LL

I o g [0/ i I W I l 1 5 i i i I g", 2' L9 b. h n my 00 o 1 m m 5 m L n. 1 m i i m 3, k "G I I I IIIII as: y l I I I i HF Lea (u 2': INVENTORS.

wlLum RGROENE HAROLD J. suexmxuu ATTORNEY.

March 5, 1940. .w. F. GROENE El Al. 2,192,436

CENTER DRIVE DOUBLE END TURRET LATHE' Filed Sept. 27, 1937 '16 Sheets-Sheet s INVENTORS. wlLum F. GROENE HAROLD I. 5\EKMmN ATTORNEY.

March 5, 1940- w. F. GROENE El AL 2,192,436

CENTER DRIVE DOUBLE END TURRET LATHE Filed Sept. 27, 1937 16 Sheets-Sheet s INVENTORS. W\\.\.H\M F. GROENE BY HAROLD lSlEKMANN ATTORNEY.

, March 5, 1940, w. F. GROENE El AL I 2,192,436

CENTER DRIVE DOUBLE END TURRET LATHE Filed Sept. 27, 1937 l6 Sheets-Sheet 7 INVENTORS. wlLum F. eaoeue HAROLD J fflEKMANN ATTORNEY.

March 5, 1940. w. F. GROENE El AL CENTER DRIVE DOUBLE END TURRET LATHE 16 Sheets- Sheet a Filed Sept. 27, 1937 WILLIAM F. GROENE BY HAROLD J. SIEKMRNN ATTORNEY.

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A mt March 5 1940. GROENEIET AL 2,192,436

CENTER DRIVE DOUBLE END TURRET LATHE Filed Sept. 27, 19:57 16 Sheets-Sheet 9 IN VENTORS.

MHLLIAM F. GROENE HAROLD J.SIEKMP\NN ATTORNEY.

W. F. GROENE ET AL March 5, 1940.

' CENTER DRIVE, DOUBLE END TURRET LATHE l6 Sh'e ets-Sheet 1O Filed Sept. 27. 1937 INVENTORS.

E w L .a mo\mt E E WILLIAM FQROENE .BY HAROLT? lSIEKMANN ATTORNEY.

l6 Sheets-Sheet 1 l ATTORNEY.

w. F. GROE NE ET AL CENTER DRIVE DOUBLE END TURRET LATHE Flled Sept 27, 1937 umm TmJ H March 5, 1940.

I/ H m P F March 5, 1940. ,w. F. GROE NE ET AL CENTER DRIVE DOUBLE END TURRET LATHE Filed Sept. 27. 1957 l6 Sheets-Sheet 1a llllllll INVENTORS. mLLmM EGROENE mow J. S\EKMP\NN v ATTORNEY.

March 5, 1940. w. F. GROENE Er AL 2,192,436

CENTER DRIVE DOUBLE END TURRET LATHE l6 Sheets-Shd 13 Filed Sept. 27, 1937 Mn w m INVENTORS. WILLIAM aarzoeue HAROLD 3.S\EKM|\NN ATTORNEY.

March 5, 1940. w. F. GROENE ET AL CENTER DRIVE DOUBLE END' TURRET LATHE Filed Sept. 27, 1937 15 Sheet s-Sheet 14 $3 mtR Q5520 TSKQQ fit :35 w

em SNA mum mam E S W uni o mm M nM ATTORNEY.

March 5, 1940. w, GRQENE AL 2,192,436

CENTER DRIVE DOUBLE END TURRET LATHE Filed Sept. 27, 1957 1a Sheets-Sheet 15 T O (D INVENTORS. wlLLlAM F. GROENE HAROLD J. SiEKMANN ATTORNEY.

March 5, 1940.

w; F. GROENE ET A]. 2,192,436

CENTER DRIVE DOUBLE END TURRET LATHE Filed sept. 27, 1937 16 Sheets-Sheet 16 INVENTORS. WILLIAM F. GROENE BY HAROLD J. S|EKMANN ATTORNEY.

UNITED STATES PATENT OFFICE.

William F. Greene and Harold J. Siekmann, Cincinnati, Ohio, assignors to The B. K. Le Blond Machine Tool Company, Ohio, a corporation of Delaware Application September 27, 1937, Serial No. 165,836

11 Claims.

This invention pertains to lathes, particularly center drive lathes adapted. to machining the end portions of shafts or similar types of work pieces. More specifically our invention is adapted to the simultaneous machining of the end portions of axle housings in a series of progressive machining operations.

An object of our invention is to provide in a lathe means for supporting and rotating a work piece intermediate its ends and to successively apply cutting tools to the end portions of said work piece to simultaneously machine said end portions thereof.

Another object ,is to provide in a lathe means.

for supporting and rotating a work piece intermediate its ends and to provide steady rest means for supporting each end of the work piece.

Another object is to provide in a lathe means for supporting and rotating a work piece intermediate its ends, steady rest means for supporting each end of the work piece, and indexing tool carrying turrets with tools adapted to progressively machine the end portions simultaneously on said work piece.

Still another object is to provide in a lathe means for supporting and rotating a work piece intermediate its ends, steady rest means for supporting each end of the work piece, and tool feeding devices associated with said steady rests adapted to perform machining operations, on the end portions of said work piece.

A still further object is to provide in a lathe means for supporting and rotating a work piece intermediate its ends, steady rest means for supporting each end of the work piece, indexing tool carrying turrets with tools adapted to machine the end portions of said work piece, and furthertool feeding devices associated with said steady rests and operated by said turrets for performing machining operations on said end portions of said work piece.

And another object is to'provide in a turret lathe automatic means'for providing predetermined feeds and speeds of work rotation for each indexed position of the turret in performingeach operation on a work piece.

Other features of our invention will be pointed out in the following description of the drawings".

in which- Figure I is a front perspective view of a center drive double end turret lathe utilizing the principles of our invention.

Figure II is a rear perspective view of the lathe shown in Figure I. I

'the speed change gearing for the work spindle or dexing turret particularly showing the operations Cincinnati,

Figure In is a left hand end elevation of the lathe shown in Figure I.

Figure IV is.a view partly in section on the line IV-IV of Figure III particularly showing center drive chuck.

Figure V is an enlarged rear elevation of the change speed gear box particularly showing the hydraulically operated speed changing mechanism. I

Figure V1 is a plan view of the left hand inperformed on the work piece and a steady rest and associated tool feeding device associated therewith for an end of the work piece.

Figure VII is a front elevation of the left hand turret shown in Figure VI.

Figure-VIII is a right hand end elevation of the-left hand indexing turret.

Figure IX is a plan view of the left hand turret.

Figure X is a vertical section on the line X- of Figure IX.

Figure XI is a vertical section on the line XI-XI of Figure 1X.

Figure XII is a vertical section on the line XII--XII of Figure IX.

Figure XIII is a rear elevation of a portion of the left hand carriage particularly showing the electric-hydraulic control apparatus associated ticularly showing the tool feeding device assovciated with a steady rest of the lathe.

Figure XVIII is anelementary diagram showing the various pieces of electrical control apparatus utilized for the lathe.

Figure XIX is a wiring diagram of the electric operating and control system.

Figure XX is a diagrammatic layout of the hydraulic and electric system to more clearly point out their inter-relation and their functions.

The general arrangement of the lathe, as shown in Figures I and 11, comprises a bed I mounted on suitable supporting legs 2, 3, and 4 upon which i I is mounted a suitable center drive head 5 which has a suitable ring gear chuck 6 adapted to support and rotate a work piece or axle housing W. Also mounted on the bed I each side of the work spindle 5 are steady rests I and 8 adapted to support the end of the work piece W. Tool feeding devices 9 and III are also respectively associated with said steady rests I and 8 and are adapted to perform machining operations on the ends of the work piece W. i

Carriages II and I2 slidably mounted on the usual ways I3 of the bed I have the respective indexing tool turrets I4 and I5 having appropriate tools which may be successively presented to the work piece W for machining the end portions thereof.

Work spindle drive Power for rotating the chuck 6 is derived from the motor I6 which is mounted on the change speed gear case II which in turn is mounted on the left hand end of the bed I. Noting particularly Figures III and IV, on the motor shaft I8 is fixed a pinion I9 which drives the idler gear 20 rotatably mounted on a suitable stud 2| fixed on the gear case II, the idler gear in turn driving the gear 22 fixed on the clutch shaft 23 rotatably mounted on appropriate anti-friction bearings 24 and 25 in the gear case I'I. Loosely joumaled on the shaft 23 is the large pinion 26 and the small pinion 2'! which are adapted to engage respective mating gears 28 and 29 ,fixed on the drive shaft 36 also joumaled in the gear case I! on suitable anti-friction bearings 3| and 32. Suitable multiple disc clutches 33 and 34 may be rendered effective to alternately cause gear 26 or gear 21 to be driven by the shaft 23 whereby the shaft 30 may be caused to rotate at different speeds by suitably rocking the rock shaft 36 having the usual yoke 31 fixed thereto for actuating the usual clutch operating spool 38 for the clutches 33 and 34. Noting Figure V, the rock shaft 36 projects outwardly through the rear of the gear case I1 and has a lever 39 fixed thereon to which is connected the piston rod 40 of a hydraulic cylinder 4I whereby the clutches 33 and 34 may be rendered effective by appropriately applying hydraulic pressure through the lines 42 and 43 of said cylinder 4|. Connected to the drive shaft 30 by a suitable coupling 44 is the shaft 45 which has its other end suitably journaled in the center drive head 5 and having the usual gearing associated therewith for driving the ring gear chuck 6.

Carriage feed mechanism Power for actuating the carriage II and I2 along the ways I3 of the bed I is derived from the hydraulic fluid pressure pump 46 (Figures II and III) mounted on and driven by the motor 41 mounted on the bracket 48 attached to the rear of the leg 2 which delivers fluid pressure through appropriate means for reciprocating the piston. 49 attached to piston rod 50 of the cylinder 5|,

Noting particularly Figures I, III, VII, and XVI, extending longitudinally along the bed I is the feed screw 6| which is suitably joumaled in the bracket 52 and has a pinion 62 engaging the rack 54 whereby reciprocation of the rack causes corresponding rotation of the screw 6|. On each of the carriages II and I2 is mounted a nut box 63 by suitable bolts 64, each of which has a rotatable nut 65 joumaled without axial movement in a suitable bearing 66 in the nut box 63 and appropriately threaded to engage the right hand screw thread 6'! for carriage II and the left hand screw thread 68 for the carriage I2. The nuts 65 are provided with an integral bevel gear 69 which is engaged by a bevel pinion III formed on the shaft 'II joumaled in the nut box 63 and which has a squared end portion 12 to which may be applied a suitable crank handle for rotating the nut 65 whereby the carriages may be adjusted axially of the screw 6| and the bed I when the screw BI is not operating. A disc I3 keyed to rotate with the shaft 'II has T slots I4 from which extend bolts 15 having clamping nuts I6 which when tightened secure the disc I3 and the shaft 1| against rotation and thereby prevent rotation of the nuts 65 when thecarriages have been properly positioned along the bed I and-are to be actuated by rotation of the screw 6| upon reciprocation of the cylinder 52 as described, the right hand thread 61 and the left hand thread 68 causing the carriages to move toward or away from each other.

Indexing turret mechanism riages a description of the left hand carriage II with its turret I4 will suffice for both.

Noting particularly Figures IX, X, In, and XII, on the carriage II is bolted a turret base 11 by bolts I8 and in which is tightly fitted a vertical stud I9. The turret I4 has an adjustable bushing 89 which is arranged to rotate snugly about the stud I9 on its bearing surfaces 8| and 82 a lock nut 83 carried on the upper end of the stud I9 serving to prevent upward movement of the turret I4 and to maintain its under surface 84 in proper sliding engagement with the thrust bearing surface 85 provided on the top of the turretbase 11 so that the turret l4 may be rotated while maintaining its proper aligned position on the carriage II.

The turret I4 is rotated by the arrangement shown in Figures IX and XII which comprises a bar 86 slidably mounted for movement parallel with the direction of carriage movement in suitable guideways 81, 88, 89, and 90 formed in the base 11. The bar 86 is normally urged to the left by a bell crank lever 9| pivotally mounted on the stud 92 carried in the base 11 which has on one of its arms 93 a rounded end 94 which engages into a slot 95 in the bar 86, a spring urged plunger 96 actuated by spring 91 suitably mounted in a hole in the base I1 serving to urge the arm 93 and thus the bar 86 to the left. On the end of the other arm 98 of the bell crank 9| is mounted a roller 99 which is caused to engage and ride up the cam surface I 09 of the block IOI fixed in a bracket I92 fixed on the bed I of the lathe when the carriage is moved away for the work piece being machined and to thereby a cavity I0'I formed in the bar 86 is a spring I08 I which engages the end of a pin I09 fixed in the outer end of the pawl I05 so as to normally urge the pawl I05 counter-clockwise about its pivot as seen in Figure IX. 0n the under side of the turret I4 is fixed a series of projecting pins IIO corresponding to the number of indexed positions to which the turret is to be moved. These pins are so placed that when the carriage II is moved to the left and away from the work the bar 86 will be moved to the right as described and cause the abutment face III of the pawl to be moved against a pin H0 and by continuing its movement against said pin to cause the turret to rotate counter clockwise as shown in Figure IX.

The cam. I00 is so arranged as to cause the bar to move suflicient to rotate the turret I4 to the next indexed position by the time the carriage has fully retracted from the ,work piece.

As the carriage again moves toward the work the bar 86 is returned to the left by spring 91, the pawl I05 being likewise carried to the left, its angular surface I I2 striking against one of the pins which has been brought to the position occupied by the pin which has just been pushed to the right or counterclockwise by the face II I of the pawl. The bar 86 and its pawl I05 continue to move to the left, the surface II2 of the pawl riding against a pin IIO swinging the pawl clockwise and compressing the spring I08. After the bar 86 has fully retracted-to the left the face 'I II of the pawl is to the left of the pin IIO.

so that the pawl snaps back counterclockwise under the influence of spring I08 in readiness for again engaging its face II I with another pin H0.

The turret is accurately indexed by the ar-' rangement shown in Figures IX and XI which comprises the indexing plunger II3 slidably mounted in guideways H4, H5, and H6 in thebase 11. The indexing faces III and H8 of the plunger I I3 are normally urged into the indexing notches II9 in the indexing ring I20, carried on the bottom of theturret I4, by a spring I2I which surrounds a pull rod I22 threaded in the end of the indexing plunger II3, and which spring bears against a portion of the base I1 and a nut I23 threaded on the outer end of the rod I22.

Mounted on therock shaft I24 carried in the base 11 is an actuating dog I25 having an upwardly extending portion with corners I26 and I21 and a downwardly extending end I 28 which is adapted to be engaged by a cam block I29 fixed on the bracket I02 when the carriage II is moved along the bed. On a projection of the rock shaft I24 is mounted a lever I30 for manually rotating the shaft I24. 'A project on I3I is provided on the lever I30 to which is attached a tension spring I32 which in turn is fastened to a pin I33 fixed in the base 'II so that the lever I30 and rock shaft I24 are normally rotated in a counterclockwise directon as seen in Figure XI. The

spring I32 is so designed as to normally maintain v the corner I28 of dog I25 engaging surface I34 of the indexing plunger II3 to withdraw it from the slot H9 in the indexing ring I20. Further movement of the carriage away from the work.

causes the-end I28 to slide along the straight surface I36 of the block I29 thus holding the indexing plunger II3 withdrawn from the ring I20 during which time the turret rotating mecha-. nism described above in Figures IX and XII is operating to rotate the turret I4 to another indexed position. At the completion of the movev ment of the carriage away from the work the end I28 has ridden off surface I36 over .the corner I I3! of block I29 allowing the indexing plunger II3 to again move toward the indexing ring I20 and enter a slot II9 under the influence. of the spring I2I. As the carriage II moves forward the end I28 again contacts the corner I 31 of block I29 and rides along the surface I36 until it drips over the corner I35 preparatory for again withdrawing the plunger II3 upon return of the carriage from the work. During this forward movement of the carriage suflicient clearance is provided between the corner I21 and face I38 I25 will have no effect on the movement of the indexing plunger II3 during forward carriage movement. By pushing downward on the lever Tooling Noting particularly Figures 1, VI, VII, and XVII, each of the turrets I4 and I5 have tools for four stages of operation on the flange ends of the axle housing W. In Figures VI and VII the first operation is that of roughing out the end of the axle housing W by longitudinally moving the roughing tools I39, I40, I4I, I42, and I43 carried on appropriate tool holders I44 and I45 fixed to the turret I4. The usual pilot bar I46 slidingin the bushing I4'I of the steady rests I and 8 serve to give added support to the turret during this roughing operation. Also in these steady rests I and 8 are the half bushings I48 and cooperating swinging caps I49 with locking bolts I50 to maintain the ends of the work in proper running support in the steady rests.

Facing or transversely moving to'olsI5I and I52 are also simultaneously applied to the work with the roughing tools for facing off the flange and end of the housing W. These facing tools that the clockwise movement of the do's.

the swinging arm I54 is a stud I56.carrying a roller I5'I'which is engaged by a slanting cam surface I58 carried on a pilot bar. I59 which, slides in a bushing I60 in the steady rest I so that when the turrets feed longitudinally toward the work the roller I51 will ride up the cam surface I58 and cause the tools I5I and I52 to be fed transversely into the work. When the turrets withdraw, the tool feeding devices 9 and I0 swing away from the work by gravity and rest against a suitable stop pin I6I and remain so disposed during the other three fin shing operations.

Upon completion of the above roughing operation the turrets I4 and I5 are indexed and fin ishing tools I62 and I63 finish bore the ends of the housing W and the tool I64 finish turns the outside. diameter of the end of the housing W these tools being carried by the turrets in appropriate tool: holders I65 and I66.

The turrets are then indexed for the third operation of finish reaming the large bore by the reamer I61 carried in the tool holder I68.

The fourth and last operation is accomplished by again indexing the turret and applying the reamer I69 in the tool holder I10 to finish ream the smaller bore in the end of the housing W.

Control mechanism This lathe is provided with electrically con trolled operating mechanism whereby predetermined different rates offeed and speed of rotation of the work being operated 'upon may be automatically obtained for each indexed position of the turrets I4 and I5. For example referring to Figures VI and VII when the roughing tools I39, I40, I4I, I42, I43, I5I, and I52 are operating a coarse feed with rapid work rotation is desirable. When the finish boring and turning tools are being used a line feed with rapid work rotation is found best. And during the finish reaming operations a coarse feed with slow work rotation is necessary to prevent chatter and provide a smooth accurate finish. These functions may all be automatically accomplished without any attention on the part of the operator by the novel mechanism to be described below.

Since both of the carriages II and I2 with their respective turrets perform the same operations it is necessary to use only one of the carriages with its turret for controlling the cycle of operation of the lathe. The left hand carriage II and its turret I4 have been selected in this lathe. On the bottom of the turret I4 as best seen Figures VIII and XV is fixed a bevel gear I1I concentric with the axis of rotation of the turret I4 by screws I12 which engages a bevel gear I13 having the same number of teeth as bevel gear I1I, this second bevel gear I13 being fixed on a shaft I14 rotatably mounted in bearings I15 and I16 formed in the base 11. The shaft I14 extends rearwardly of the carriage II and base 11 and has fixed on its outer end a. gear I11 which meshes with a like gear I18 fixed to a dog carrying drum I19 by screws I80, the drum in turn being rotatably mounted on a stud I8I driven in a bore I82 formed in the rear face of the carriage II the outer end of the stud I8| being supported by a bracket I83 extending outward from and being fastened to the rear of the carriage II by bolts I84. By this arrangement the drum I19 is caused to rotate in exact synchronism with the rotation of the turret I4.

Bolted to the drum I19 are dogs I85, I86, and I81 which engage and actuate the roller arms I88, I89, and I90 of the respective limit switches LSI, LS-3, arid LS4.

Limit switch LS-I is for effecting the change of speed. of work rotationand controls the solenoids I90a. and I90b of the hydraulic valve I9I, Figure XX, whereby fiuid pressure delivered through lines I92, I93, and I94 may be directed to either line 42 or 43 of cylinder 4| for rendering one or the other of the clutches 33 or 34 ef-' fective to cause a speed change for the center drive gear as described. By properly positioning the dog I85 on the drum a low or a high speed of work rotation may be automatically obtained for any indexed position to which the turret I4 may be rotated. This limit switch LS-I is to be held closed while the clutch 33 is operative for high spindle speed and to be open for low spindle speed, this limit switch controlling appropriate 'a,192,4se

relays which in turn cause proper operation of the solenoids Ia and I90b of the valv I9I.

Limit switch LS--3 is a normally closed switch which is actuated by the dog I86 on the drum I 19. This dog I86 is so positioned as to hold the switch LS3 open only when the turret is indexed to the first operation or loading position to prevent the forward feed solenoid I of the feed direction control valve I96 from being automatically energized. After the work piece W has been changed and the main driving motor I6 has been started, it will be necessary to throw the hand lever I91 of the control valve I96 to the forward feed position to start the carriages feeding toward the work W, but from this point the solenoid I 95 will be automatically operated at the beginning of the second, third, and fourth operations. The purpose of this switch 18-3 is to prevent automatic operation at the loading station and to bring the feeding cycle to a stop at the beginning of the first operation.

Limit switch LS--4 is a normally closed limit switch which is operated by the dog I81 on the drum I19 which is so positioned as to open the limit switch LS4 for approximately M of asecond as the turret turns between the fourth operation position and the first operation position. This limit switch when so actuated stops the main driving motor I6 at the completion of the machining'cycle. This switch must again be closed by the time the turret has fully turned to the loading or first operation position so that when the starting push button I98 Figure I is pressed the spindle starts rotating for the next machining cycle.

Limit switch LS-2 is a normally open switch which is carried on a bracket I99 bolted to bracket I83 by bolts 200. On the bed I of the lathe is bolted a support -20I by bolts 202 and 203 to which in turn is bolted a feed and rapid traverse selector valve 204 by bolts 205 which also pass through and support a plate 206. On this plate 206 is mounted a bar 201 by a screw 208 which carries near one of its ends a dog pin 209 which is adapted to engage and actuate the roller arm 2I0 of the limit switch LS2 to hold it closed each time the carriage is fully retracted from the work to allow indexing of the turret. This permits energizing the forward feed solenoid I95 of control valve I96 to begin the feeding operations toward the work piece W.

Limit switch 15-5 is a normally open switch and is located, Figures III and XX, on the bracket 52 andhas its roller lever 2 so positioned as to be engaged by a .dog pin 2I2 fixed in bracket 55 so that when the cylinder 5| has been actuated to bring the tools fully. forward against the work and at the end of the cutting operation this switch LS-5 will be closed. Closing this switch starts a timing relay which energizes the rapid traverse reverse solenoid 2I3 of control valve I96 at the end of the predetermined timing period to return the tools from the work W.

Operating cycle After the work or axle housing W has been properly chucked up in the center drive chuck 6 and adjusted in the steady rests 1 and 8 the push button station I 98 is operated to start the main drive motor I6 in operation to rotate the center drive chuck. In this particular illustrative set-up the dog I85 is so arranged as to actuate limit switch LSI for operating valve I9I to cause fast spindle rotation during the first 

